1. Field of the Invention
The present invention relates generally to an apparatus and method for preventing an acoustic shock. More particularly, the present invention relates to an apparatus and method for preventing an acoustic shock hazard to users of a portable terminal.
2. Description of the Related Art
An acoustic shock to a portable terminal, which results to a user typically from hearing an unexpected loud sound via a telephone such as a portable terminal, are sometimes referred to as Acoustic Incidents, may interfere with voice signals being transmitted or received during a phone call, thus making it difficult to accurately receive the content of the phone call. Also, a sudden acoustic shock may cause a headache, an auditory damage, and/or a temporary auditory trouble. Additionally some people might experience shock, nausea and anxiety. The headaches, fatigue, and hypersensitivity to loud noise and tinnitus (ringing sound in the ears) may continue unabatedly for days, or weeks. Thus, the acoustic shock is recognized as a serious problem both by users and manufacturers of portable terminals.
An acoustic shock preventing apparatus has been developed in an attempt to solve the problem of acoustic shock. However, because the conventional acoustic shock preventing apparatus considers and processes only a frequency of a specific tone component of an input signal, it is not effective for an acoustic shock such as a white noise that is generated as a large signal over the entire frequency band. In fact, the problem of acoustic shock is particularly unsolved with regard to digital data, and with users of portable terminals sometimes wearing ear buds or headsets, the potential for discomfort or injury is greater than ever.
Also, the conventional acoustic shock preventing apparatus can provide the best performance when applied to the last stage of a receiver path. However, when an additional gain is present at a rear end of a portable terminal, it may cause the problem of an additional tuning issue in the conventional acoustic shock preventing apparatus.